armv7: Add emulation/qemu-armv7 board.

To simplify testing ARM implementation, we need a QEMU configuration for
ARM. The qemu-armv7 provides serial output, CBFS simulation, and full
boot path (bootblock, romstage, ramstage) to verify the boot loader
functionality.

To run with QEMU:
 export QEMU_AUDIO_DRV=none
 qemu-system-arm -M vexpress-a9 -m 1024M -nographic -kernel build/coreboot.rom

Verified to boot until ramstage loaded successfully by QEMU v1.0.50.

Change-Id: I1f23ffaf408199811a0756236821c7e0f2a85004
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2354
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/cpu/Kconfig

@@ -3,6 +3,7 @@
 # (See also src/Kconfig)
 if ARCH_ARMV7
 
+source src/cpu/armltd/Kconfig
 source src/cpu/samsung/Kconfig
 
 endif	# ARCH_ARM

src/cpu/Makefile.inc

@@ -2,6 +2,7 @@
 ## Subdirectories
 ################################################################################
 subdirs-y += amd
+subdirs-y += armltd
 subdirs-y += intel
 subdirs-y += samsung
 subdirs-y += via

src/cpu/armltd/Kconfig

@@ -0,0 +1,8 @@
+config CPU_ARMLTD_CORTEX_A9
+	depends on ARCH_ARMV7
+	bool
+	default n
+
+if CPU_ARMLTD_CORTEX_A9
+source src/cpu/armltd/cortex-a9/Kconfig
+endif

src/cpu/armltd/Makefile.inc

@@ -0,0 +1 @@
+subdirs-$(CONFIG_CPU_ARMLTD_CORTEX_A9) += cortex-a9

src/cpu/armltd/cortex-a9/Kconfig

@@ -0,0 +1,5 @@
+config BOOTBLOCK_CPU_INIT
+	string
+	default "cpu/armltd/cortex-a9/bootblock.c"
+	help
+	  CPU/SoC-specific bootblock code.

src/cpu/armltd/cortex-a9/Makefile.inc

@@ -0,0 +1,2 @@
+ramstage-y += cache.c
+romstage-y += cache.c

src/cpu/armltd/cortex-a9/bootblock.c

@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2013 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+void bootblock_cpu_init(void);
+void bootblock_cpu_init(void)
+{
+}

src/cpu/armltd/cortex-a9/cache.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2013 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <common.h>
+#include <system.h>
+#include <armv7.h>
+
+/*
+ * Sets L2 cache related parameters before enabling data cache
+ */
+void v7_outer_cache_enable(void)
+{
+}
+
+/* stubs so we don't need weak symbols in cache_v7.c */
+void v7_outer_cache_disable(void)
+{
+}
+
+void v7_outer_cache_flush_all(void)
+{
+}
+
+void v7_outer_cache_inval_all(void)
+{
+}
+
+void v7_outer_cache_flush_range(u32 start, u32 end)
+{
+}
+
+void v7_outer_cache_inval_range(u32 start, u32 end)
+{
+}